热压罐成型工艺典型框架式工装热分布与变形模拟

THERMAL DISTRIBUTION AND DEFORMATION SIMULATION OF TYPICAL FRAME TOOLING IN AUTOCLAVE MOLDING PROCESS

本文对复合材料热压罐成型的典型框架式工装进行热分布与变形仿真分析,结果表明:在罐内循环气体的作用下,热压罐中工装存在迎风面和背风面,迎风面的温度率先升高,随着升温过程的推进,工装温差不断加大,当升温结束时,工装的温差达到最大。实际生产中要想减小工装之间的温度差异,可以适当增加低温阶段的保温平台。对于结构复杂的框架工装,实际的热分布结果与经验认知存在差异,领先与滞后区并非分布在罐头和罐尾处。将温度结果作为边界条件计算变形可以得到:热压罐内温度梯度的存在导致工装发生热膨胀变形,最大变形基本都位于四个边角位置,最大变形量约为0.9 mm,这主要是Invar的热膨胀系数较小的缘故。在实际制造中,选择Invar钢作为模具材料是很好的选择,它可以有效减小复合材料固化过程中的固化变形。

In this paper,the thermal distribution and deformation simulation of typical frame tooling for composite autoclave molding are carried out.The analysis results show that:Due to the role of circulating gas in the autoclave,there are windward and leeward sides in the autoclave,and the temperature of windward side first rises.During the heating process,the temperature difference of the tooling increases continuously.When the temperature rise stage ends,the temperature difference of the tooling reaches to the maximum state.In order to reduce the temperature difference in the tooling,an insulation platform can be added.For the tooling with complex frame structure,there are differences between the actual heat distribution results and the empirical cognition,the leading and lagging regions are not distributed in the head and tail area of the tank.Taking the temperature results as boundary conditions,it can be obtained that:Due to the existence of temperature gradient in autoclave,the thermal expansion deformation of tooling occurs.The maximum deformation is basically located at four corners,and the maximum deformation is about 0.9 mm,which is mainly due to the small thermal expansion coefficient of Invar steel.In actual manufacturing,it is a good choice to choose Invar steel as the mould material,which can effectively reduce the curing deformation of the composite during the curing process.